Semi-automatic magazine gun



April 13, 1965 T. w. sPAcK SEMI-AUTOMATIC MAGAZINE GUN 2 Sheets-Sheet 1Filed Aug. 28, 1961 INVENTOR.

THEODORE W. SPACK iiiuiiuil .lllii 1 1 ATTORNELS April 13, 1965 T. w.SPACK SEMI-AUTOMATIC MAGAZINE GUN 2 Sheets-Sheet 2 Filed Aug. 28. 1961ATTORNEYS United States Patent U 3,177,863 SEMI-AUTOMATIC MAGAZINE GUNTheodore W. Spock, Webster Groves, Mm, assignor to This inventionrelates to semi-automatic magazine guns of the gas operated type and isparticularly related to certain improvements in such guns hereinafterset forth.

The guns of the general class here involved have been heretofore verycomplicated in construction, difiicult to assemble or service, and quiteexpensive. Such guns have also had the problem of lack of efficient andeconomical use of the gas applied to propel the pellets and also recockthe hammer. While the use of the main propelling gas for recocking thefiring mechanism is not exactly new, the means herein disclosed to makethe gas useable for that purpose is thought to be new and unique and itis a general object of this invention to provide a simple and directacting mechanism which is adapted to recock the firing means in a gasoperated gun and make it a semiautomatic gun.

It is also a general object of this invention to provide asemi-automatic gas gun with light weight and simple operating means sothat the cocking action of the same will respond to the recocking cyclesubstantially instantaneously and with positive assurance of reachingthe proper positions, whereby the cumulative effect of inertia ofseveral parts can be reduced and rendered less significant.

A preferred embodiment of the invention is disclosed herein and is seento include a spring loaded hammer which operates a gas valve to releasea charge of gas for propelling a pellet from the breech end of the shottube. The hammer is formed with a portion subject to the gas charge forthe purpose of using the pressure to return the hammer to its cockedposition. Since the action of the hammer and the gas charge is veryrapid, the cocking action means associated with the usual trigger ismade light weight to reduce inertia and gain responsiveness withoutsacrifice of sturdiness. In the embodiment disclosed, there are fewparts which must interact to release the hammer and then recock thehammer upon its return movement. These means are provided with resilientelements to govern the movement thereof and produce rapid response sothat semi-automatic operation is easily obtained and recocking of thehammer is achieved with each trigger action.

These and other features of the invention will become more fullyunderstandable as the description of a preferred embodiment proceeds.Other objects of the invention will be seen to reside in theorganization of parts and components set forth in the claims andreference thereto will be made in the following description andaccompanying drawings, wherein:

FIG. 1 is a longitudinal elevational View, with portions broken away andother portions shown in sectional elevation of a gun constructed andcomposed of the parts and components embodying the improvements of thisinvention;

FIG. 2 is a top plan view of the gun of FIG. 1, with portions brokenaway;

FTG. 3 is a fragmentary side elevational view showing a portion of thegun of FIG. 2; and

FIG. 4 is a fragmentary sectional elevational view of the gun of FIG. 1,but illustrating certain parts and components thereof displaced toillustrate the operation thereof. 7

The general organization and construction of the gun 3,l77,3d3 CePatented Apr. 13, 1965 and its novel cocking mechanism is shown toadvantage in FIGS. 1, 2 and 3. The gun 10 is constructed of a tubularbody ll closed at the muzzle end by a threaded plug 12 and closed at therear end by a stop plug 13 secured therein by a set screw 14, althoughthe stop plug may be threadedly mounted if desired. The tubular body 11is divided into a gas chamber 15 by means of a bulkhead or diaphragm 16held in position by a lock ring 17. The diaphragm 16 is formed with anaperture 18 opening to an adjacent valve chamber 19. The valve chamberIt? is formed between the diaphragm l6 and a partition in this case inthe form of a valve block 20, the latter block being secured in positionby a ferrule 21 threaded through a side of the tubular body 11 into aside of the block, thereby providing a gas outlet passage communicationwith an axially formed passage 22 in the block 20. The gas valve side ofblock 20 is sealed to the body tube 11 by an O ring 23, and the adjacentend of the axial passage 22 is formed with a seat 24. The valve block 26and the stop plug 13: define the limits of a hammer chamber 25, and thischamber is accessible through a hammer latch slot as at the bottom andthrough a side slot 27 (see FIG. 3) in which there is a divergent notch28. Both slots will be described presently.

The gun is provided with a cover tube 29 which is secured to the bodytube 11 in any suitable manner, as by soldering or the like. The covertube houses a barrel tube 30 which extends from the muzzle end 31 of thecover tube rearwardly to a breech end portion 32 which is defined by anannular land 33 fitted snugly within the cover tube 29 and provided withan O ring seal 34 to prevent escape of the gas charge. The cover tube 29also houses a magazine tube 35 extending inwardly from its open rear end36 to an inner end in abutment with the breech end of the barrel tube35. The inner end of the magazine tube 35 carries a suitable 0 ring seal37 and between the seal 37 and the breech end 32 there are formed aplurality of spaced ports 38 which open radially to the magazine fromthe annular space between the cover 29 and the magazine tube 35. Thereare three sets of radial ports 38 spaced apart a distance substantiallyequal to the axial length of the pellets P to be used in the gun. Eachset of ports 38 opens into a circumferential groove in which there isdeposited an O ring element 39. The breech end 32 of the barrel tube 30is formed with diarnetral ports 46 which open to the annular spacebehind the land 33 and this space communicates with the ferrule 21.

It may be seen in FIG. 1 that the body 11 houses a valve 41 supported inthe valve chamber 19 upon a forwardly extending guide 42 which fitsloosely in the aperture 18 of the diaphragm 16. The valve 41 is alsooperatively supported by a hammer strike pin 43 movable in the axialpassage 22. A valve closing spring 44 is mounted on the guide 42 to urgethe valve to closed position over the seat 24. The strike pin 43 fitsloosely in passage 22 so that an extension or tubular piston 45 on theforward end of hammer 46 may slide within passage 22 and be sleeved overthe pin 43. The inner end 47 of the extension serves as the strikingsurface for the strike pin 43. Hammer 46 reciprocates in hammer chamber25 and is axially bored at 43 to receive a hammer spring 49 which isguided by rod 54) secured at its base end in the stop block 13 by theset screw 14. The hammer 46 has a forward face 51 which moves over theslot 26 in the body tube 11, and a side of the hammer (FIG. 3) movesover the side slot 27 (see FIG. 3) and is exposed thereby so that ahammer cocking lever 52 may be passed through the slot 27 and secured tothe hammer body for manually moving the hammer as will be referred topresently.

The gun It is provided with a hand grip or stock 53 which is secured tothe body tube if by the set screw 14 and by a second set screw 54engaged in a locating element 55 fixed to the body 11 adjaecnt thetrigger guard 56. The grip 53 is suitably formed to provide a chamber 57for the operating mechanism now to be described.

Still referring to FIG. 1, the operating mechanism comprises a trigger53 pivoted at 59 and formed with a finger 6t? engaged by a triggerreturn spring 61. A safety elerner 62, of usual construction is locatedadjacent the finger 6% to prevent trigger actuation when desired. Ahammer latch element 63 is pivoted at 64 so that the latch projection 65extends through the slot 26 so that its sloping surface is in the pathof hammer face 51. A suitable spring 66 engages latch 63 and urges thesame upwardly as shown to hold the hammer 46 in cocked position. Latch63 is held in hammer cocking position by means of a latch block 67 whichhas spaced legs 68 (one leg being broken away for clarity of disclosure)which are pivoted at the free ends on pin 69. The upper solid end 70 ofthe latch block 67 is formed with a finger 71 which cooperates with thelatch as to retain it in hammer cocked position as shown. However, thelatch 63 is formed with a notch 72 to receive the finger when the gun isfired. The latch block 67 is urged by a suitable spring 73 to theposition shown with the finger 71 out of and at the right of the notch72.. A pawl element 74 is pivoted at 75 on the trigger finger 6t andextends into engagement with the end '79 of latch block 67. Suchengagement is effected by a pawl shoulder 76 engaging the end 7 t9 sothat a projection 77 extends between the legs 63 to provide lateralsupport and guidance for the pawl. The pawl is resiliently supported onspring 78 and is thereby urged upwardly to maintain the shoulder 76 inengagement with the latch block 67. In addition to the foregoing partsand elements, the latch 63 is formed with a projection 7% which atcertain times when the latch 53 is depressed by the hammer so forces thepawl 7 downwardly in opposition to spring 73 and frees the latch block67 for rapid movement under the urging of spring 73.

The organization of the mechanism and the construction of the severalparts is such that the moving parts are light weight for very rapidresponse to the action of the high pressure gas charge during firing andequally rapid recovery under urging of the several springs. The parts 63and 74, are of substantially uniform thickness and have the sideelevation configuration as shown. The part d7 is bifurcated to form thelegs 68 which staddle the pivot 6h. The gas charge is obtained from astandard type bottle 39 charged with CO gas at about 800 p.s.i. The CSbottle St) is inserted in chamber 15 with its nozzle 61 away from thediaphragm 16 so that when the threaded plug 12 is screwed into place apiercing pin 32 is aligned with the nozzle.

Loading operation The foregoing gun It) is loaded with a supply ofpellets P by first withdrawing the follower plunger 83 from the magazinetube 35 at end 36. This is accomplished by pulling the handle 84rearwardly along a slot 85 in the side of the cover 29 and magazine tube35 until the follower 83 is free to be turned to rest on the end of stopblock 13. The handle 84 is connected to a spring loaded tension rod 36(PEG. 2) which slides in a tube 87 along side the cover tube 29, and thetube 87 houses an elongated spring 33 which is fixed at the end 89 ofthe tube 37. The opposite end of the rod carries a plug 9% which isengaged by the spring 83 so that the spring tends to urge the plug 9%toward the muzzle end 31 and thereby force the pellets P into the breechend 32 of the barrel tube 3t) as shown in PEG. 1.

A suitable number of pellets P are dropped into the magazine 35 and thefollower 83 is again placed in the end 36 of the magazine. The spring 88will force the follower to push the pellets P into the position shown inFIG. 1 and in so doing the 0 rings 39 will form seals at the leadingpellets except that one in the breech 32.

Gas charging The gun is charged with the CO gas by first moving thehammer 46 by cocking lever 52 to cocked position where the latch 65 isheld in front of the hammer face 51 by latch block finger 71 engagingthe surface 71a adjacent notch 72. At this point the pawl 74 will haveits shoulder 76 engage the head 7E9 of the latch block 67 and thetrigger 58 will be in cocxed position. The hammer is then rotated tosafety position by aligning the cocking lever 52 with the notch recess28 (FIG. 3) and pushing the lever 52 into such recess. This prevents thehammer from moving forward. The trigger safety device 62 may also beused if desired. With the hammer 46 thus on safety, the plug 12 may beremoved and a C0 bottle 8% placed in the chamber 15. The plug 12 isreplaced and threaded down tight so that the pin 82 punctures the bottlenozzle 81. After this the plug is backed on about one-half turn towithdraw the pin 82. The hammer 46, or trigger 58, as the case may be,may be taken off safety and the gun is ready to be fired.

Firing Operation Referring now to FIG. 4 and to FIG. 1 for comparison,it is seen that the gun Ill is fired by pulling trigger 58 which movespawl 74 rearwardly to push the latch block 67 against spring 73 untilthe finger 7ll aligns with latch notch 72. This frees the latch 63 whichis forced downwardly as the hammer face 51 rides over the sloping faceof latch projection 65. The hammer spring 49 drives the hammer 46forwardly and slides the tubular extension 45 thereon over the strikepin 43 until the face 47 hits the end of pin 43 and urges the pinrightwardly to open valve ll against spring 44. The spring guide 42 alsomoves rightwardly as it is permitted to slide in the diaphragm aperture18. The gas charge in chamber 19 flows through passage 22 and outferrule 21 to the breech ports 4%. At the same time the gas charge actson the end of the hammer extension 45 as if it were a piston and drivesthe hammer back to its cocked position. The pellet P is expelled as thegas charge on reaching the breech 32 is sealed in by 0 rings 34 and 37so that no escape along the cover tube 29 occurs. However, as theleading pellet P is discharged along the barrel 313 the gas flows intothe series of radial ports 38 and compresses the 0 ring seals 39 aboutthe three next following pellets P to retain such pellets against beingforced backwardly in the magazine 35. Thus the greater proportion of theenergy from the gas charge is made available for propelling the leadingpellet P, and a suflicient portion of the energy is utilized to recockhammer 46.

Recocking operation The hammer recocking is achieved by the action ofthe latch 63 being depressed against its spring 66 to force the pawl '74to disengage its shoulder 76 from the latch block head 70. This actionof the pawl 74 is caused by the latch projection 79 engaging on'the pawland forcing the same down against the pawl spring 78. As the returninghammer face 51 clears the sloping face of the latch projection 65, thelatch rises under actionof spring 66 and lifts the notch 72 off thelatch block finger 71. The latch block 67 is thereby free to moverightwardly under urging of its spring '73 so that the finger 71 againengages latch surface Illa and holds the latch 63 in raised position infront of the hammer face 51. During this action of the parts the trigger58 can be held pulled back with no undesired effect since the pawl 74 isnow in a position with'its shoulder 76 disengaged from the head 74) ofthe latch block 67. Release of the trigger 5% permits the trigger spring61 to recoek the trigger which pulls the pawl 74 rightwardly until pawlspring 7 8 resets the shoulder 76 on the latch block head 70. Theforegoing oper- 3,1 vases ation occurs automatically each time thetrigger is pulled and released.

The foregoing description of operation has been given with reference toFIGS. 1 and 4 as these views of the drawing serve to illustrate thedifferent phases of the operation of the mechanism. In view of the abovedescription of operation it should be clearly understood in what mannerthe preferred mechanism is caused to operate and thereby provide asemi-automatic gun in which each trigger operation serves to discharge apellet P and simultaneously effect recocking of the hammer 46.

It will be apparent from the above details of description of theinvention that the same fulfills the objects thereof as previously setforth, and while the preferred embodiment is susceptible to change andalteration, it is not desired to limit the scope of the invention toprecisely those disclosed details, except as the same may be necessaryby the appended claims.

What is claimed is:

l. A gas-powered semi-automatic gun comprising a barrel having a breechend, a source of gas under pressure, passage forming means leading fromsaid gas source to said breech end, a valve operably controlling theflow of gas through said passage forming means, a valve operating hammermovable between a cocked position and a valve open position, pistonmeans on said hammer movable in said passage forming means with an endface exposed to gas pressure upon opening of said valve by said hammer,the gas pressure causing hammer movement to said cocked position, and atrigger and trigger operated mechanism in the gun adjacent the path ofhammer movement, said mechanism including a latch normally holding saidhammer in cocked position, a latch block cooperating with said latch toretain the latch in hammer cocked position, an element connected to saidtrigger and movable with the trigger to engage and displace said latchblock from cooperation with said latch and release said hammer, andmeans movable with said latch upon hammer release to engage said elementand retain said element out of engagement with said latch block upontrigger movement releasing said hammer, said mechanism responding tosaid hammer movement under gas pressure toward cocked position toposition said latch to hold said hammer in cocked position and saidlatch block to cooperate with said latch.

2. A gas-powered semi-automatic gun comprising a barrel having a breechend, a source of gas under pressure, passage forming means leading fromsaid gas source to said breech end, a valve operably controlling theflow of gas through said passage forming means, a valve operating hammermovable between a cocked position and a valve open position, pistonmeans on said hammer movable in said passage forming means with an endface exposed to gas pressure upon opening of saidvalve by said hammer,the gas pressure causing hammer movement to said cocked position, and atrigger and trigger operated mechanism in the gun adjacent the path ofhammer movement, said mechanism including a latch normally holding saidhammer in cocked position, a latch block cooperating with said latch toretain the latch in hammer cocked position, and an element connected tosaid trigger and movable with the trigger to engage and displace saidlatch block from cooperation with said latch and release said hammer, aresilient member for each of said latch, latch block and element, saidresilient members being effective to locate said latch, latch block andelement in hammer cocked attitude and render the gun automaticallyrecocking, and means on said latch positioned to engage said elementupon hammer release and retain said element out of engagement with saidlatch block upon trigger movement releasing said hammer, said mechanismresponding to said hammer movement under gas pressure toward cockedposition to position said latch to hold said hammer in cocked positionand said latch block to cooperate with said latch.

3. In a gas-powered semi-automatic gun a body having a hammer chamber, avalve block closing one side of said chamber, said valve block having apassage therein communicating with a source of gas under pressure andopening to said chamber, a hammer in said chamber, a valve controllingthe flow of gas through said passage, a valve operating strike elementon said valve extending into said passage, means on said hammerextending into said passage and forming a piston subject to the gaspressure, said means on said hammer being a tubular extension sleeved onsaid valve strike element and reciprocating in said passage, saidtubular extension means being adapted to engage said strike element toopen said valve and admit gas to the passage, resilient means in saidchamber adapted to drive said hammer from a retracted position towardsaid valve block and cause said tubular extension means to open saidvalve and admit gas under pressure to reversely move said hammer to saidretracted position, a hammer latch pivoted on the gun in position toproject into said hammer chamber and latch said hammer in its retractedposition, a latch block movable in one direction to retain said latch inhammer latched position and movable in an opposite direction to releasethe hammer latch, a trigger, and means responsive to trigger actuationto move said latch block in said opposite direction to release saidlatch.

4. In a gas-powered gun: a tubular body open at its opposite ends; ablock in said body between the ends dividing the body into two spaces,said block having a through passage therein opening to the body spacesand an angularly directed passage opening outwardly of said body; abarrel tube carried by said body and having a connection with saidangular passage; one of said body spaces containing gas under pressure;a hammer in the other one of said body spaces; means closing the openends of said body; resilient means in said hammer containing space inposition to displace said hammer toward said block; trigger mechanismoperatively mounted on said body adjacent said hammer containing space,said mechanism including a trigger, a hammer latch projecting into thelast mentioned body space, and latch controlling means selectivelyoperable to hold said latch projecting into said body space to retainsaid hammer in a cocked position independently of said trigger and torelease said latch in response to trigger action; and means operativelymounted in said block to control the gas pressure release to saidangular passage and to block gas flow to said hammer containing space,said control means including a flow control valve adjacent the gas spaceside of said block having an actuating stem extending into said throughpassage, resilient means urging said valve to close the passage, anextension on said hammer projecting into said through passage and beingmoved by said resilient hammer displacing means to strike said valveactuating stem and open said valve, said hammer extension blocking gasflow in said through passage and, in turn, being forced by the gas underpressure outwardly to return said hammer against its resilientdisplacing means, said latch catching said hammer on its returndisplacement, and latch block means urged to a position to retain saidlatch in its hammer catching position.

5. A gas powered semi-automatic gun comprising a barrel having a breechend, a source of gas under pres- I sure, passage forming means leadingfrom said gas source to said barrel breech end, a hammer chamber, saidpassage forming means having a branch passage opening to said hammerchamber, a valve operably controlling the flow of gas through saidpassage forming means, strike pin means on said valve extending intosaid branch passage, a valve closing spring engaged with said valveopposite said strike pin means, a valve opening hammer in said hammerchamber movable between a cocked position and a valve open position,said hammer including valve operating piston means projecting from saidhammer and slidable in said branch passage over said strike pin meanswith an end face exposed to gas pressure in said passage forming meansupon opening of said valve by said piston means, said piston means andstrike pin means blocking gas flow into said hammer chamber so that gaspressure acts on said end face to force said hammer to return to cockedposition, a trigger, and trigger operated mechanism in said gun adjacentthe path of hammer movement, said mechanism having a first settingnormally holding said hammer in its cocked position, and a secondposition upon trigger operation releasing said hammer for movement toits valve open position, said mechanism responding to said hammermovement toward its cocked position to automatically catch said hammerat its cocked position.

6. In a gas powered semi-automatic gun, a body formed to provide a valvechamber and a hammer chamber, a valve block member separating saidchambers and having a passage therein opening between said chambers, ahammer in said hammer chamber, a valve in said valve chamber closing theadjacent end of said passage, a valve actuating member on said valveextending into said passage toward said hammer chamber, a tubular hammerextension telescoping over said valve actuating member and projectinginto said passage and constituting a piston for said hammer, said pistonextension having a surface therein for striking said actuating member toopen said valve, a source of gas under pressure communicating with saidvalve chamber, spring means driving said hammer in valve openingdirection and causing said surface in said piston extension to strikesaid valve actuating member opening said valve to release gas underpressure into said passage and cause operation of said hammer extensionas a piston to return said hammer against said spring means, saidtubular hammer extension and valve actuating member being interfitted toclose the valve block passage to flow of gas to said hammer chamber, anda trigger and trigger operated mechanism for the gun arranged adjacentsaid hammer chamber to automatically retain said hammer in its returnposition.

7. In a gas powered gun, a frame having spaced hammer and gas chambers,a barrel tube adjacent said chambers having a breech end to receiveprojectiles, a member in said frame having a first passage open to saidbreech end of said barrel tube, said member having a second passage openat one end to said gas chamber to receive gas under pressure and open atthe opposite end to said hammer chamber, said first passage being opento said second passage between the said ends of said second passage,valve means controlling said one end of the second passage, a valveactuating hammer in said hammer chamber and including an extensionthereon slidably fitted in said second passage between said opposite endof said second passage and the opening of said first passage to saidsecond passage, said extension having an end face exposed to the gasunder pressure when said valve means admits ga under pressure into saidfirst passage, means between said valve means and hammer to operate saidvalve upon hammer movement in a direction to slide said extension towardsaid first passage, the gas under pressure forcing said extension toreverse direction and drive said hammer back, a trigger to initiatehammer movement to operate said valve means, and means be tween saidtrigger and hammer to efiect initiation of said hammer movement andarrest thereof upon completion of reversal of direction, said last meansincluding a hammer latch, a latch block normally holding said latch inhammer arrest position, an element moved by said trigger to displacesaid latch block from its normal position, and means on said latcheffective in hammer unlatche'd position to disable said element andtrigger While said latch block is out of its normal position.

8. In a gas-powered semi-automatic gun, a tubular housing having itsopposite ends closed by removalble plug means, means in said housingforming a partition between said plug, means dividing the same intochambers and providing a through passage between said chambers, saidwall means also having a lateral passage opening outwardly of saidtubular housing from said through passage, a barrel tube mounted on saidtubular housing having a breech end adjacent the said lateral passage tocommunicate therewith, a source of gas under pressure in a first one ofsaid chambers, a spring powered hammer in the second one of saidchambers, valve means carried by said Wall means with its head in saidfirst chamber on the gas source side of said through passage and a valvestrike pin extending in said through passage toward the second chamber,a tubular extension on and moved by said hammer and slidably fitted intosaid through passage and telescoped over said strike pin so that the endof said extension is exposed in said through passage to gas pressure,said extension and strike pin substantially preventing the loss of gaspressure into said second chamber and said extension actuating saidvalve to open the same, said hammer in said second chamber being movablebetween a cocked position and a firing position in which said valve isopened, a slot in the wall of said second chamber traversed by saidhammer, and gun firing mechanism mounted adjacent said slot andincluding a latch movable in said slot to hold said hammer in its cockedposition, said latch being automatically responsive to hammer movementto relatch said hammer in its cocked position after firing, and saidtubular extension on said hammer responding to gas under pressure anddriving said hammer rearwardly from its firing position to its cockedposition.

9. In a gas-powered semi-automatic gun: a barrel tube having a shotreceiving breech end; a source of gas under pressure; passageway meansconnecting the gas source with said breech end; a valve controlling theflow of gas in said passageway; a hammer movable between a cockedposition and a shot firing position; a piston extension on said hammerslidably fitted in said passageway and cooperating with said valve toopen said valve upon hammer movement to said shot firing position, theopening of said valve allowing gas under pressure to force said pistonextension to move to return said hammer to cocked position; and a firingtrigger and trigger operated mechanism adjacent said hammer, saidmechanism including a latch movable out of and into a hammer cockingposition and having a recess and solid surface adjacent thereto and aprojection adjacent said solid surface, a latch block movably mountedadjacent said latch and having a finger thereon normally engaged uponsaid solid surface to hold said latch in hammer cocked position, anelement movable with said trigger and adapted to engage said latch blockand move the latter to a position with its finger received in said latchrecess whereby said hammer is freed to move to shot firing position andsaid latch projection strikes said element to dischgage said latchblock, and separate spring means for said latch, latch block andelement, said spring means normally urging said latch into hammercocking position, said latch block into position with its finger on thesolid surface of said latch and said element normally in position ofengagement with said latch block so as to be responsive to triggeroperation to initiate firing of the gun, said latch projection acting tohold said element out of latch block engagement so that said latch isfree to respond to its spring means to catch said hammer upon return tococked position and said latch block is free to respond to its separatespring to move its said finger into engagement on said solid surface ofsaid latch and establish recocking of saidhammer.

References Cited by the Examiner UNITED STATES PATENTS LOUIS R. PRINCE,P imary Examiner.

RICHARD C. PINKHAM, Examiner.

1. A GAS-POWERED SEMI-AUTOMATIC GUN COMPRISING A BARREL HAVING A BREECHEND, A SOURCE OF GAS UNDER PRESSURE, PASSAGE FORMING MEANS LEADING FROMSAID GAS SOURCE TO SAID BREECH END, A VALVE OPERABLY CONTROLLING THEFLOW OF GAS THROUGH SAID PASSAGE FORMING MEANS, A VALVE OPERATING HAMMERMOVABLE BETWEEN A COCKED POSITION AND A VALVE OPEN POSITION, PISTONMEANS ON SAID HAMMER MOVABLE IN SAID PASSAGE FORMING MEANS WITH AN ENDFACE EXPOSED TO GAS PRESSURE UPON OPENING OF SAID VALVE BY SAID HAMMER,THE GAS PRESSURE CAUSING HAMMER MOVEMENT TO SAID COCKED POSITION, AND ATRIGGER AND TRIGGER OPERATED MECHANISM IN THE GUN ADJACENT THE PATH OFHAMMER MOVEMENT, SAID MECHANISM INCLUDING A LATCH NORMALLY HOLDING SAIDHAMMER IN COCKED POSITION, A LATCH BLOCK COOPERATING WITH SAID LATCH TORETAIN THE LATCH IN HAMMER COCKED POSITION, AN ELEMENT CONNECTED TO SAIDTRIGGER AND MOVABLE WITH THE TRIGGER TO ENGAGE AND DISPLACE SAID LATCH